diff --git a/src/add-ons/translators/pngtranslator/PNGTranslator.cpp b/src/add-ons/translators/pngtranslator/PNGTranslator.cpp
index 32834db993..db380dbf89 100644
--- a/src/add-ons/translators/pngtranslator/PNGTranslator.cpp
+++ b/src/add-ons/translators/pngtranslator/PNGTranslator.cpp
@@ -325,6 +325,14 @@ PNGTranslator::translate_from_png_to_bits(BPositionIO *inSource,
 		int bit_depth, color_type, interlace_type;
 		png_get_IHDR(ppng, pinfo, &width, &height, &bit_depth, &color_type,
 			&interlace_type, int_p_NULL, int_p_NULL);
+
+		if ((color_type == PNG_COLOR_TYPE_GRAY ||
+			color_type == PNG_COLOR_TYPE_GRAY_ALPHA) && bit_depth < 8) {
+			// libpng's gray to RGB conversion is not implemented
+			// for bit depths less than 8
+			result = B_NO_TRANSLATOR;
+			break;
+		}
 		
 		// Setup image transformations to make converting it easier
 		bool balpha = false;